Accelerated Solvent Extraction Technique Research Articles

Native and TMT Chestnut Extractives as Hydrophobic and Photostabylizing Additives for Wood Surfaces

Wood extractives have proven strong anti-oxidative properties which may be used to mitigate surface deterioration caused by photolytic effects and free radical formations. An interesting challenge regarding wood extractives is understanding how they behave in terms of treating natural wood surfaces to reduce anti-oxidative processes that arise from exposure to the main environmental factors. In this study, the possible efficacy of chestnut (Castanea sativa Mill.) extractives derived from native (CH) and thermally modified wood (TMT CH), as a means of protecting against UV exposure in poplar (Populus spp.) and spruce (Picea abies Karst.) wood, was evaluated. Chestnut wood was first thermally modified at 180 °C for 3 h, and the extractives were obtained by the accelerated solvent extraction technique (ASE) and subsequently used to treat wood surfaces. Samples were immersed in extractive solutions and exposed to artificial UV-weathering exposure, then contact angle and colour stability were monitored during the process. An FTIR analysis of the photo-degradation process of poplar and spruce surfaces was also executed. Extractives of TMT chestnut changed the total colour variation in both poplar and spruce wood. A much darker colour compared to the extractives of native wood was observed and an increase in ∆E* from 9.75 to 30.76 and 6.24 to 22.97 in poplar and spruce was calculated. The stability of the colour depended both on the surface wood and the type of extractive. The initial contact angle remained almost unchanged in the poplar wood surface and only slightly increased in spruce regardless of whether they were treated with extractives from native or TMT chestnut wood. A strong reduction in contact angle after the accelerated UV exposure test was observed, especially in spruce treated with CH extractives. FTIR analysis confirmed the lower levels of chemical degradation of surfaces observed by colorimetry, where TMT CH extractives formed more stable chemical bonds than native extractives. The comparative analysis in this study clarified the complex relationships between the effects of high-temperature modification of wood and the potential protective role of TMT extractives on some wood surfaces.

Cellulose fibers and ellagitannin-rich extractives from rambutan (Nephelium Lappaceum L.) peel by an eco-friendly approach

This study assesses the viability of an accelerated solvent extraction technique employing environmentally friendly solvents to extract ellagitannins while producing cellulose-rich fibers from rambutan peel. Two sequential extraction protocols were investigated: 1) water followed by acetone/water (4:1, v:v), and 2) acetone followed by acetone/water (4:1, v:v), both performed at 50 °C. The first protocol had a higher extraction yield of 51 %, and the obtained extractives featured a higher total phenolic (531.4 ± 22.0 mg-GAE/g) and flavonoid (487.3 ± 16.9 mg-QE/g) than the second protocol (495.4 ± 32.8 mg-GAE/g and 310.6 ± 31.4 mg-QE/g, respectively). The remaining extractive-free fibers were processed by bleaching using either 2 wt% sodium hydroxide with 3 wt% hydrogen peroxide or 4–5 wt% peracetic acid. Considering bleaching efficiency, yield, and process sustainability, the single bleaching treatment with 5 wt% of peracetic acid was selected as the most promising approach to yield cellulose-rich fibers. The samples were analyzed by methanolysis to determine the amount and type of poly- and oligosaccharides and studied by 13C solid-state nuclear magnetic resonance spectroscopy and thermal gravimetric analysis. The products obtained from the peels demonstrate significant potential for use in various sectors, including food, nutraceuticals, cosmetics, and paper production.

Gamma rays induced enhancement in the phytonutrient capacities of tomato (Solanum Lycopersicum L.)

One of the most important problems for the field-grown Ayaş tomato (Solanum lycopersicum Ayas population), which is preferred for consumption in Central Anatolia because of its aromatic taste, is that the shelf life is short because of insufficient fruit firmness. Therefore, a study was initiated to develop high-quality lines and variety candidates through mutation breeding in the current Ayaş population. In this study, the effective mutation dose (EMD50) was found to be 150 Gy for seeds using a Cobalt-60 gamma ray source. The main mutant population was generated by applying EMD50. During the study, mutant lines selected by following the classical mutation breeding stages were evaluated in terms of yield and quality traits (antioxidant content, total soluble solid amount, fruit firmness, Brix, etc.) starting from the M4 stage. One of our aims was to determine and improve the phytonutrient content of field-grown tomatoes. The fruits of selected lines at the M4 stage were extracted by liquid-liquid partition and accelerated solvent extraction techniques and analyzed by High Performance Liquid Chromatography (HPLC) in this study. It was found that 28 of the 29 mutant lines were significantly different from the control and mutant lines. Mutant lines 9-22, 8-90, 8-135, and 8-127 were determined to be the most promising for commercialization.

Characterization of the anti-AChE potential and alkaloids in Rhizoma Coptidis from different Coptis species combined with spectrum-effect relationship and molecular docking.

Coptis species are the main source of Rhizoma Coptidis (RC) drugs, which have always been used to treat Alzheimer's disease in the clinical experience of ancient China. However, many species of this genus have been largely underutilized until now. With this fact, this research has been designed to investigate for the first time the anti-acetylcholinesterase (AChE) property of different extracts for RC drugs from four Coptis species (C. chinensis, C. deltoidea, C. teeta and C. omeiensis) and to quantify the main alkaloids. Petroleum ether, ethyl acetate and n-butanol fractions of RC drugs were sequentially collected using an accelerated solvent extraction technique. Spectrum-effect relationship and molecular docking were applied to analyse the relationships between alkaloids and AChE inhibitory activity. The N-butanol extract was proven to be the main active fraction, and C. teeta may be the best source of RC drugs for Alzheimer's disease treatment, with significantly lower IC 20, IC 50 and IC 80 values for AChE inhibition. The UPLC/QqQ-MS quantitative analysis showed that the accumulations of 10 alkaloids in RC drugs from different sources greatly varied. Three data processing methods (Random forest, Boruta and Pearson correlation) comprehensively analysed the spectrum-effect relationship and revealed that columbamine, berberine and palmatine were the most important AChE inhibitors that could be used as quality markers to select RC drugs for Alzheimer's disease treatment. In addition, the dominant compounds were successfully docked against AChE to verify the binding affinity and interactions with the active site. The present study can contribute to the reasonable development and utilization of RC drugs from different sources, especially to provide certain evidence for their application in the treatment of Alzheimer's disease.

Optimizing accelerated solvent extraction combined with liquid chromatography-Orbitrap mass spectrometry for efficient lipid profile characterization of mozzarella cheese

In this study, a novel Accelerated Solvent Extraction (ASE) procedure combined with UHPLC-Q-Orbitrap-MS was developed for detailed untargeted lipid profile of mozzarella cheese. Response Surface Methodology and Pareto front, using a Central Composite Design (CCD), were employed to define the optimised combination of extraction temperature, number of extraction cycles and mix of solvents. LipidSearch™ software was used for a reliable and accurate lipid identification. A total of 13 subclasses, including ceramides, diacylglycerols, triacylglycerols, lysophosphatidylcholines, lysophosphatidylethanolamines, phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, sphingomyelins, bismethyl phosphatidic acids, cholesterol ester, zymosterol ester, hexosyl ceramides were measured. The elaboration of the CCD showed that the solvents ratio was the main factor affecting the extraction efficiency. The optimised ASE method, together with the Folch extraction, synergistically contributed to a complete characterization of lipid profile of mozzarella cheese, confirming ASE technique, associated with high resolution mass spectrometry detection, as an efficient tool for Lipidomics in food science.

Targeted analysis of sea buckthorn oil extracted by accelerated solvent extraction technique using green and conventional solvents

Sea buckthorn oil (SBO) was extracted using accelerated solvent extraction with two green solvents (ethanol and 2-methyltetrahydrofuran), and two petroleum-based solvents (hexane and diethyl ether) at four different temperatures (60, 90, 120 and 150 °C), using one extraction cycle at 103.42 bar, 10 min static time, 5 min preheating and 30% flushing volume. β-carotene and α-tocopherol were quantified jointly using HPLC-UV/VIS and the fatty acid profile was analyzed using GC-MS. Extraction yield was also measured and the data was compared to a conventional extraction using Soxhlet. The extraction with ethanol achieved significantly higher concentrations of β-carotene in the final oil (1.67 mg/g oil) compared to the results of any other solvent (e.g. 1.23 mg/g oil for hexane ASE) or to the conventional extraction (1.27 mg/g oil). However, the use of green solvents led to the dragging of unwanted polar compounds (sugars), leading to lower oil yield values after purification.

Optimization of the Efficient Extraction of Organic Components in Atmospheric Particulate Matter by Accelerated Solvent Extraction Technique and Its Application

Organic components in atmospheric fine particulate matter have attracted much attention and several scientific studies have been performed, although most of the sample extraction methods are time consuming and laborious. Accelerated solvent extraction (ASE) is a new sample extraction method offering number of advantages, such as low extraction cost, reduced solvent and time consumption, and simplified extraction protocols. In order to optimize ASE methods to determine the concentrations of organic compounds in atmospheric fine particulate matter, different parameters were set out for the experiment, and the optimal method was selected according to the recoveries of the standard (i.e., n−alkanes and polycyclic aromatic hydrocarbons (PAHs)). This study also involves a comparison of the optimal method with the traditional method of ultrasonic extraction (USE). In addition, the optimized method was applied to measure the mass concentrations of organic compounds (n−alkanes and PAHs) in fine particulate matter samples collected in Beijing. The findings showed that the average recovery of target compounds using ASE was 96%, with the majority of compounds falling within the confidence levels, and the ASE recoveries and precision were consistent with the USE method tested. Furthermore, ASE combines the advantages of high extraction efficiency, automation, and reduced solvent use. In conclusion, the optimal ASE methods can be used to extract organic components in atmospheric particulate matter and serve as a point of reference for the development of analytical methodologies for assessing organic compounds in atmospheric particulate matter in China.

A novel green extraction and analysis technique for the comprehensive characterization of mangiferin in different parts of the fresh mango fruit (Mangiferaindica)

The study reports a novel, green, and effective ASE (accelerated solvent extraction) technique with a green, fast, and sensitive method of UPLC-MS/MS for a comprehensive characterization of whole mango fruit (epi-, endo-, Mesocarp, seed) under solvent, temperature, and origin effect in order to determine the inter- and intra-variation of MG(Mangiferin)-amount in fresh mango fruit. The ASE-MD (method development) showed the highest extract yield and more MG-amount in H2O at 80 °C (mesocarp fruit part). For MG-quantification, a fast and sensitive UPLC-MS/MS method (RT = 0.31/runtime = 1 min; m/z 421.10 → 81.00 amu) was developed. The UPLC-MS/MS-MV validated the method with high accuracy, precision, and r2 = 0.998. The intra-variation for MG was: mesocarp > endocarp > epicarp > seed. The inter-variation (MG-amount (mg/10g) in 12-mango cultivars) based on the sum of MG-amount/12-mango fruits parts: mesocarp (12.42)> epicarp (10.92)> endocarp (10.47)> seed (8.70) whereas, based on the largest MG-amount/individual mango fruit it was: mesocarp (5/12 fruits)> endocarp (4/12 fruits)> epicarp (3/12 fruits)> seed (0/12). The statistical models for PCA, K-mean cluster, and Pearson's analysis revealed significant correlation (P ≤ 0.005) for origin*solvent*temperature Vs MG-amount with a nonsignificant correlation for origin*MG-amount Vs extract yield. The ASE-UPLC-MS/MS comprehensively characterized inter-, and intra-variation of MG in different parts of mango fruit.

Accelerated Solvent Extractions (ASE) of Mitragyna speciosa Korth. (Kratom) Leaves: Evaluation of Its Cytotoxicity and Antinociceptive Activity.

Mitragyna speciosa Korth (kratom) is known for its psychoactive and analgesic properties. Mitragynine is the primary constituent present in kratom leaves. This study highlights the utilisation of the green accelerated solvent extraction technique to produce a better, non-toxic and antinociceptive active botanical extract of kratom. ASE M. speciosa extract had a dry yield (0.53–2.91 g) and showed a constant mitragynine content (6.53–7.19%) when extracted with organic solvents of different polarities. It only requires a shorter extraction time (5 min) and a reduced amount of solvents (less than 100 mL). A substantial amount of total phenolic (407.83 ± 2.50 GAE mg/g and flavonoids (194.00 ± 5.00 QE mg/g) were found in ASE kratom ethanol extract. The MTT test indicated that the ASE kratom ethanolic leaf extract is non-cytotoxic towards HEK-293 and HeLa Chang liver cells. In mice, ASE kratom ethanolic extract (200 mg/kg) demonstrated a better antinociceptive effect compared to methanol and ethyl acetate leaf extracts. The presence of bioactive indole alkaloids and flavonols such as mitragynine, paynantheine, quercetin, and rutin in ASE kratom ethanolic leaf extract was detected using UHPLC-ESI-QTOF-MS/MS analysis supports its antinociceptive properties. ASE ethanolic leaf extract offers a better, safe, and cost-effective choice of test botanical extract for further preclinical studies.

لا يوجد عنوان بالعربي في ملف الطلب على النظام

The thriving terror activity is a menace to our society. To mitigate this, there is a dire need of upgraded and innovative analytical techniques for forensic analysis of explosives. The complexity in the matrix, restrictions in the sample quantity and ambiguity in the data interpretation are the different challenges that a forensic scientist face. The solution to these problems lies in upgradation of extraction technique, screening technique & confirmatory techniques. In this paper, the identification and forensic analysis of post blast residues recovered from controlled blast site has been presented. The targeted sample was extracted from soil by using Accelerated Solvent Extraction technique. The target compound was primarily identified to be PETN (PentaErythritol TetraNitrate) by color test and TLC (Thin Layer Chromatography). The confirmatory test for the target analyte was done by using a hyphenated technique LC-MS/MS (Liquid Chromatography Mass Spectrometer with tandem Mass). This manuscript demonstrates the viability of LC-MS/MS in Forensic Science for a fast, accurate and quality-assured analysis of post-blast residue.

Optimization of extraction and quantification technique for phenolics content of garlic (Allium sativum): An application for comparative phytochemical evaluation based on cultivar origin.

A range of conventional, i.e. maceration, percolation, ultrasonic assisted, Soxhlet and Soxtec extraction (STE), to advanced extraction techniques of accelerated solvent extraction (ASE) was utilized for the first time in order to optimize the extract yield and recovery of phenolics-gallic acid (GA), rutin (RT) and quercetin (QT)-quantified via ultra-high performance liquid chromatography with diode array detector (UHPLC-DAD). The effect of solvents (n-hexane, dichloromethane and methanol) and temperature (60, 80 and 100°C) upon extraction yield, phenolic content and antioxidant activity (DPPH, ABTS and DPPH) was studied, and the method was validated in commercial food samples from Saudi Arabia, China and India. A high extract yield with percentage recovery was observed for STE (1221.10 mg/5 g; 24.42%) and ASE techniques (91.50 mg/1 g; 9.15%) in methanol at 100°C. UHPLC-DAD showed retention times (min) of 0.67, 1.93 and 1.90 for GA, RT and QT, respectively in the shortest runtime of 3 min. The yield for phenolics was higher for STE/ASE (ppm): 15.27/15.29 (GA), 85.24/37.56 (RT) and 52.20/33.40 (QT), respectively. In terms of antioxidant activities, low IC50 values (μg/ml) of 1.09/1.18 (DPPH), 2.11/5.32 (ABTS) and 4.35/7.88 (phenazine methosulfate-nicotinamide adenine dinucleotide) were observed for STE and ASE, respectively. Multivariate analysis for STE showed a significant (P = 0.000) correlation for extraction type vs. extract yield and phenolics content; however, there was no significance for antioxidant activities vs. extraction type. ASE showed a positive correlation for solvent vs. extraction yield, phenolics and antioxidant activity; however, there was no correlation for extraction yield and DPPH activity. Principal component analysis for STE showed a major variability (52.02%) for extraction yield and phenolics in PC1 followed by PC2 (38.30%) for antioxidant activities. For ASE, PC1 (48.68%) showed a positive correlation for solvent vs. extraction yield and phenolics while PC2 (33.12%) showed a positive correlation for temperature and antioxidant activities. STE and ASE were the optimized extraction techniques for the garlic food sample while a significant effect of solvent and temperature was observed upon extraction yield, phenolics and antioxidant activity.

Extraction, Characterization and Application of Cashew Nut Shell Liquid from Cashew Nut Shells

In this study, cashew nut shell liquid has been extracted from cashew nut shells using an accelerated solvent extraction technique and was employed as a precursor for the synthesis of cashew nut shell liquid resin. The extract was a dark brown viscous liquid with an average yield of 30.61±0.200%. Results of the physical analysis showed a moisture content of 4.45±0.020% and a density of 0.95±0.300 gcm-3. The percentage brix and refractive index were 76.20±0.001 and 1.47 ±0.010 respectively. Chemical characterization showed a pH of 5.65±0.003; acid value of 8.25± 0.200 mg KOH/g; ash content of 1.80±0.6%; free fatty acid of 4.12±0.400 mg KOH/g; ester value of 247.01±0.100 mg KOH/g and a saponification value of 255.26±0.800 mg KOH/g. The FTIR spectra revealed that cashew nut shell liquid is polymeric. These findings confirm that higher phenolic compounds which can be used as potential precursors in industrial applications could be obtained from agro wastes.
 Practical Applications: Cashew nut shell liquid, an extract from cashew nut shell, an agro waste has a wide range of functional products. A practical application is synthesis of a high viscous, flexible cashew nut shell liquid resin with physical properties that are consistent with literature and could also be further used in other industrial applications. Further processing of cashew nut shell for the development of value added products like resin can be a better option.

Development of Thai Gac Fruit Extraction as a Multifunctional Cosmeceutical Ingredient for Antioxidant, Melanogenesis and Collagen Stimulating Activities

Gac fruit (Momordica cochinchinensisSpreng) is mostly found in southeast Asian countries. Previous studies have demonstrated that gac fruit is a major source of β-carotene, lycopene, and α-tocopherol. This study aimed to develop the extraction of Thai gac fruit as a potential active ingredient for antioxidant, melanogenesis, and collagen stimulating activities. In the present study, different parts of ripe Thai gac fruit, the peel, pulp, and seed membrane, were extracted using the accelerated solvent extraction (ASE) technique, an innovative plant extraction method. DPPH radical-scavenging activity, ABTS radical scavenging activity, and ferric reducing/antioxidant power (FRAP) assay were performed to compare the antioxidant activity derived from each part of the fruit. The effect of Thai gac fruit on melanogenesis and collagen stimulating activities was investigated using B16F1 and human fibroblast cell lines, respectively. The results demonstrate that the pulp (EC50value of 7.42 ± 0.81 mg/mL) and the seed membrane (EC50value of 76.43 ± 2.66 μg/mL) showed the strongest antioxidant activities in DPPH and ABTS assay, respectively. The peel clearly displayed the strongest antioxidant activity and significantly increased the FRAP value (247.67 ± 19.73 μM/mg). Furthermore, the peel showed the lowest melanin content (76.56 ± 7.13 % of control) in the B16F1 cell line, and clearly increased the most amount of collagen (21.87 ± 3.12%) in the human fibroblast cell line in comparison to the other fractions. Therefore, Thai gac fruit peel revealed the biological effects, including antioxidant, melanogenesis, and collagen stimulating activities. In conclusion, Thai gac fruit extracted using the ASE technique exhibited several effects that could be used as a potential active ingredient for cosmeceutical products, due to its antioxidant, melanogenesis, and collagen stimulating activities. Our findings provide potential uses of Thai gac fruit as a multifunctional cosmeceutical ingredient to be further explored in future studies.

Comparison of different extraction methods for polysaccharides from bamboo shoots (Chimonobambusa quadrangularis) processing by-products.

The aim of this study was to evaluate the influences of extraction methods on the yield, chemical structure and antioxidant activity of polysaccharides from bamboo shoots (Chimonobambusa quadrangularis) processing by-products (CPS). CPSs were extracted by using five methods including hot water extraction (HWE), accelerated solvent extraction (ASE), ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE) and enzyme-assisted extraction (EAE). The experimental results showed that the uronic acid contents, monosaccharide contents, molecular weights and antioxidant activities of the five CPSs were significantly different. CPS extracted using ASE method (ASE-CPS) possessed the highest extraction yield (9.94%), the highest medium-high-molecular-weight value (136.07 kDa) and notable antioxidant ability. UAE-CPS had the highest uronic acid (9.42%) and the lowest medium-high-molecular weight value (117.49 kDa), and its antioxidant activity was the best. Based on the correlation analysis, the higher uronic acid content, smaller molecular weight, and lower content of monosaccharide composition of glucose for the CPS-UAE might contribute to its higher antioxidant activity. From an industrial viewpoint, ASE technique could be a promising and alternative way to extract CPS due to its high yield, notable antioxidant activity, and convenient industrialization.

Extraction Optimization of Phenolics and Antioxidants from Black Goji Berry by Accelerated Solvent Extractor Using Response Surface Methodology

This study aims to provide fundamental knowledge for the use of black goji berry and determine the optimum process parameters that produce maximum phenolics from black goji berry through accelerated solvent extraction (ASE). The optimal extractions of phenolics and antioxidants from black goji were explored via the ASE techniques, applying the response surface methodology (RSM) design. After reaching the optimal conditions for single factors, the optimal ASE extraction conditions were found through a total of 17 runs following the Box-Behnken design (BBD) from RSM. The maximum yield of total phenolic content (TPC) was 17.92 mg GAE/g under the best extraction conditions: an extraction temperature of 89.38 °C, an ethanol concentration of 70% and an extraction time of 13 min. This study indicates that the optimal extraction conditions could serve as the scientific basis for scaled-up industrial production. Black goji berry could be a viable source of nutraceuticals due to the abundance of antioxidant and phenolic substances.

N-Alkane and long-chain alcohol recovery in moose (Alces alces), a browsing herbivore

Habitat management for herbivores often depends on an understanding of the food habits of animals. Plant cuticular waxes containing nearly indigestible complex mixture of n-alkanes and long-chain alcohols (LCOHs) have recently shown promise for diet analyses, but the accuracy of the technique depends strongly on the efficiency of recovery of the markers in feces. Fecal recovery of n-alkanes and LCOHs from 10 browse stems or leaves and two ensiled grass hays fed to moose (Alces alces (Linnaeus, 1758)) during in vivo digestion trials was investigated. n-Alkanes and LCOHs were extracted using a single-step accelerated solvent extraction technique and the recovery of these cuticular components was calculated from the feces of the animals. n-Alkane recoveries from feces averaged 0.82, ranging from a low of 0.58 (haylage) to a high of 0.95 (browse stems). LCOH recoveries averaged 0.92 across all forages, ranging from 0.80 (haylage) to a high of 1.13 (browse stems). n-Alkane and LCOH fecal recovery increased with increasing chain length, similar to findings in other studies. Although fecal recovery of n-alkanes and LCOHs were variable, we conclude that they are inversely related to forage digestibility, are consistent within forage classes, and are therefore predictable markers for use in assessing herbivore diets.

Development and validation of an HPLC method with fluorescence detection for the determination of fluorescent whitening agents migrating from plastic beverage cups

ABSTRACTAn HPLC method with fluorescence detection has been developed and validated for the quantification of six fluorescent whitening agents (FWA) in plastic beverage cups after extraction and in food simulants after migration at 70°C for 2 h. The sensitivity of the method was high with LODs ranging from 0.053 to 0.251 μg kg−1 and LOQs from 0.107 to 0.504 μg kg−1. Accuracy and precision were highly acceptable, with recoveries greater than 82% and RSDs (%) below 16%. The expanded combined uncertainty was found to be less than 23% for the measurements of all studied FWAs. In extracting the analytes from food contact materials (FCM), accelerated solvent extraction (ASE) and Soxhlet extraction were applied using ethanol as the extraction solvent. The results obtained for FWA in 10 different food plastic cups, made from different polymers, were compared. The ASE technique proved to be faster, more effective and efficient than Soxhlet extraction. Migration tests with official food simulants from Regulation (EU) No 10/2011 showed that the substances studied could potentially migrate using the selected migration conditions. The most pronounced effect was observed in case of simulant D1 (50% w/v ethanol in water). The analytical method proved to be a simple, fast, sensitive and reliable tool for the simultaneous quantification of six of the most used FWAs in both FCM extracts and food simulants after migration experiments.

Leaf wax n-alkane extraction: An optimised procedure

Leaf wax n-alkanes are often extracted from modern plant material to describe their natural occurrence and understand the factors determining their potential as biomarkers for climate reconstruction. Despite several studies on the topic no standardised approach for n-alkane extraction from leaves has been yet devised. A common issue is the necessity to work on leaf subsamples to reduce co-extraction of unwanted polar compounds (e.g. chlorophyll), as they often interfere with individual steps involved in post-extraction, wet-chemical isolation of leaf wax n-alkanes. However, subsampling can generate biases regarding n-alkane distribution, concentration, and isotopic composition due to heterogeneities along the leaf sheath. Therefore, we propose and test an optimised extraction approach. Using leaves of Cladium mariscus and Typha angustifolia, we compared the effect on n-alkane extraction of two solvent mixtures, two extraction techniques and two sample preparation modalities. We found similar results for the two modes of sample preparation (intact vs. shredded leaf), while the use of the two solvent mixes and the two extraction techniques produced significantly different results. n-Hexane/dichloromethane 9:1 was almost twice as efficient (+97%) than the more commonly used dichloromethane/methanol 9:1, producing higher n-alkane yields while reducing co-elution of highly polar compounds. The best results, both for yield, sample processing time and solvent consumption, were achieved in combination with the accelerated solvent extraction technique, averagely +49% more efficient than ultrasound assisted solvent extraction. Alongside, we investigated the distribution of n-alkanes along the leaf sheath of C. mariscus.

Novel fast analytical method for indirect determination of MCPD fatty acid esters in edible oils and fats based on simultaneous extraction and derivatization

A novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatization in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of analytes released from esterified forms from the water phase and as dilution solvent for solid PBA – the derivatization agent. It is a noteworthy improvement of recommended indirect approaches available in the literature because such steps as sample clean-up, multiple liquid–liquid extractions, and preconcentration are excluded in the proposed solution. In this way, the developed procedure is shortened and simplified. Such an approach also minimizes the utilization of organic solvents; therefore, it is in accordance with the principles of “green analytical chemistry.” In spite of the fact that the step of sample clean-up is omitted, no deterioration in GC-MS system performance was observed. Equivalence testing of the developed procedure and AOCS cd 29b-13 official method (SGS) has been conducted. It was concluded that results obtained by both methods do not significantly differ statistically. The procedure has been applied to determination of MCPD esters concentrations in lipid fractions isolated by accelerated solvent extraction technique from such foodstuffs as bakery products, salty deep-fried snacks, and instant products. In all investigated samples, the level of bound MCPD was elevated. Additionally, for both procedures, the environmental impact (with the use of analytical Eco-scale) and uncertainty budget have been assessed and compared.

Characterization of nucleobases in sea buckthorn leaves: An HPTLC approach

ABSTRACTThe present study aims to establish a high-performance thin layer chromatography (HPTLC)-based comparative analysis, directed toward characterization of nucleobases in aqueous and alcoholic extracts of sea buckthorn leaves from three different varieties: Hippophae salicifolia, Hippophae rhamnoides mongolica, and Hippophae rhamnoides turkestanica. The alcoholic and aqueous leaf extracts from these sea buckthorn varieties were prepared using accelerated solvent extraction technique. A novel HPTLC method for separating and identifying six nucleobases, namely, guanosine, guanine, cytosine, adenine, uracil, and thymine were adopted. HPTLC analysis indicated the presence of one or more of these nucleobases in a total of six leaf extracts evaluated, their quantities varying from 0.23 to 7.76 µg nucleobase per mg of extract. Though a typical trend could not be observed in the values obtained, the extracts were found to be considerably rich with respect to nucleobase contents. The results acquired from HPTLC were subsequently validated by hyphenation with mass spectrometry and also by applying chemometric tools in form of heat maps, hierarchical cluster dendrograms, and principal component analysis. The presence of nucleobases in the leaf extracts was confirmed by HPLC as well but HPTLC proved to be a better approach for characterization of nucleobases in plant extracts, than high performance liquid chromatography (HPLC).